Vending machine control circuit having multifunction switches



United States Patent inventor James F. Ptacek Kansas City, Missouri Appl. No. 758,187 Filed Sept. 3, 1968 Patented Nov. 17,1970 Assignee The Vendo Company Kansas City, Missouri a corporation of Missouri VENDING MACHINE CONTROL CIRCUIT HAVING MULTIFUNCTION SWITCHES 9 Claims, 2 Drawing Figs.

U.S. Cl 194/10 Int. Cl G07t'll/00 Field of Search... 194/2, 10

(56] References Cited UNITED STATES PATENTS 3,349,881 10/1967 Camp 194/10 3,409,110 11/1968 Baum 194/10 Primary Examiner-Stanley H. Tollberg Atrorney- Schmidt,Johnson, Hovey, Williams and Chase ABSTRACT: In a multiple selection vending machine, the sold-out functions for individual dispensing columns and all columns, along with the cancellation of credit during each vend, are accomplished by a single switch associated with each column and a solid state switching arrangement common to all of the columns. The arrangement utilizes a triac that controls the coin return electromagnet, gate current for the triac being drawn through the selection solenoids of the columns by an OR circuit having current limiting resistors that prevent the magnitude of the current from reaching a level that would energize the solenoids.

Patented Nov. 17, 1970 3,540,562

' INVENTOR 9 James F. Pfacek BY W VENDINGMACI-IINE CONTROL CIRCUIT HAVING MULTIFUNCTION SWITCHES This invention relates to improvements in control apparatus for vending machines of thegeneral type disclosed and illustrated in the U.S. Pat. of Elmer C. Johnson, No. 3,348,733, granted Oct. 24, I967 and owned by the assignee herein. Vending machines of this type dispense a product by the momentary actuation of a selection or vend solenoid associated with each dispensing column of themachine. It is customary to provide means for individually preventing operation of the vend solenoids as the associated columns become depleted of products and for rejecting coin deposits whenall columns are sold out.

ln order to effect the individual column and overall sold-out functions, two sold-out" switches are normally associated with each column, one for the individual sold out function and the other, in conjunction with corresponding switches of the other columns, for the overall sold out function to sense depletion of products in all of the columns. Such machines are also customarily provided with switches for cancelling the established credit once a product is dispensed, one switch being associated with each column respectively for operation when that column is selected for dispensing by the customer. Thus, three necessary functions requiring three separate switches are involved in the control of each column, thereby rendering the cost and complexity of the switching arrangement directly proportional to the number of columns provided.

It is, therefore, the primary object of this invention to provide a multiple function switching arrangement for a vending against gravitation from the platform 16. The gate 38 is mounted on a pivot rod 40 and is provided with a projection 42 which is movable into engagement with the actuator arm 44 of a sold-out switch 46. A return spring 48 biases the gate 38 in a counterclockwise direction toward the position thereof shown in broken lines. It should be understood that the solenoid 18 is shown deenergized andthat such solenoid shifts its armature 20 to the left upon energization thereof, a return spring (not shown) for the armature 20 being employed to effect rightward movement thereof to the position illustrated upon deencrgization ofthe solenoid 18.

In HO. 1 the control circuitry for a three-column vending machine is illustrated. The circuitry is shown in standby awaiting the deposit of money and selection of a column of products by a customer. Since the control components for each individual column are identical, only one column will be described in full, corresponding components of'thc other columns being identified bylike reference numerals with the addition of the a or b notation.

A suitable alternating current supply is connected across power terminals 50 and 52 from which lines 54 and 56, respectively, extend. A push button selector switch 58 is associated with the vend solenoid 18, the solenoid hold switch 32, and the sold-out switch 46 of the first column, the selector switch 58 being connected in series laddered relationship with the selector switches 58a and 58b of the two other columns. A lead 60 connects the normally open contact of switch 58 to the normally closed contact of sold-out switch 46, the normally open contact of the latter being connected to the power terminal 50 by a sold-out lamp 62.

machine of the above type which effects a reduction in the cost of the machine. and also simplifies the control circuitry thereof. and wherein a greater proportionate saving in cost is realized as the number of columns (and hence selections) increases.

As a corollary to the foregoing object, it is an-important aim of the instant invention to provide such an. arrangement wherein the three control functions for each column discussed above are handled by a single switch associated with each column in conjunction with a common switching component for all columns.

Furthermore, a specific and important object of this invention is to provide a means for controlling the coin-return electromagnet in the coin acceptor of the machine utilizing a solid state switch under the. control of an OR circuit that samples current through a mechanical sold-out switch and the vend solenoid of each column.

In the drawing:

FIG. 1 is an electrical schematic diagram of the control circuitry; and

FIG. 2 is a fragmentary, vertical sectional view of a column of a serpentine can vendor showing an exemplary dispensing mechanism. 1

Referring initially to FIG. 2, the dispensing mechanism A solid state control device in the nature ofa triac 64 has its cathode-anode switching terminals connected to line 54 and a coin return clectromagnet 66 respectively, the other electrical side of the CREM 66 being connected to the other line 56. The CREM 66 is located in the coin acceptor (not shown) of the coin controlled mechanism of the vending machine and, when energized, permits deposited coins to pass through the acceptor channels and become accepted if valid. When deenergized, the CREM 66 commonly operates appropriate coin diverter structure (not shown) which rejects the deposited coins and returns the same to the customer.

The triac 64 has a gate 68 which presents the control connection therefor, the gate 68 being connected by a current limiting resistor 70 to the normally closed contact ofa singlepole switch 72. The switch 72, a second single-pole switch 74, and a relay coil 76 comprise the components of a credit relay which establishes credit in response to operation of a coin switch 78. It should be understood that the coin switch 78 comprises a simplified, exemplary illustration since oftentimes coin totalization would be required that would involve the employment of a totalizer responsive to the coinage deposited by broadly denoted I0. is similar in its structural configuration to the mechanism shown and described in the above-mentioned U.S. Pat. No. 3,348,733. Only the bottom of the column is illustrated, there being the usual compartment wall 12 separating the column from the next adjacent column (not shown). A serpentine support ramp 14 for the articles in the column terminates at its lower end at an inclined dispensing platform 16 beneath which the components of the dispensing mechanism 10 are mounted.

A vend solenoid 18 has its armature 20 connected to a pivotal stop 22 by a link 24. Thestop 22 is mounted on a pivot rod 26 with its' upper end normally disposed in an opening 28 in platform 16. The upper end ofthe stop 22 has a downturned flange and, in the position illustrated, such flange bears against the actuator arm 30 ofa solenoid hold switch 32.

The lower end of the stop 22 is provided with a roller 34 engageable with a tab 36 on a swingable article delivery member or gate 38 illustrated in full lines in its standby position retaining the lowermost of the articles A (shown in phantom lines) immaterial to the instant invention, thus coin switch 78 may be assumed to be responsive to the deposit and acceptance of a coin of suitable denomination representing the vend price of the various articles in the machine. In order for such coins to effect operation of switch 78, it is requisite that the coin return electromagnet 66 be energized, otherwise deposited coins are returned to the customer.

Three current limiting resistors 80, 80a and 80b comprise a part of an OR circuit and are connected between the movable pole of relay switch 72 and the normally open contacts of selector switches 58, 58a and 58b respectively. The normally open contact of switch 72 is connected by a lead 82 to the anode of a diode 84, the cathode thereof being connected to The SCR 88 'controls the energization of the coil 76 of the credit relay, the coil 76 being connected in series between line 54 (via lead 96) and the anode of SCR 88. A diode 98 is connected across the relay coil 76 for purposes of transient suppression. The three solenoid hold switches 32, 32a and 32b are connected in series laddered relationship between the movable pole of relay switch 74 and a lead 100 that connects to the movable pole of the selector switch 58b. A resistor 102 is connected between the movable pole of relay switch 72 and the lead 100.

OPERATION ln standby before the deposit of coinage and the making ofa selection by a customer, the triac 64 is conducting and thus the CREM 66 is energized. Assuming that none of the columns of the machine are depleted, the sold-out switches 46, 46a and 465 are in the positions shown. Therefore, gate current for the triac 64 flows through all of the vend solenoids 18, 18a and [8b, the path through solenoid 18 being as follows: From line 56 to solenoid l8, through the sold-out switch 46, along the lead 60 to resistor 80, and through relay switch 72 and resistor 70 to the gate connection 68. It is evident that similar parallel paths are traced through the other vend solenoids 18a and 18b via the respective current limiting resistors 80a and 80b, The resistors 80, 80a and 80b serve to limit the magnitude of the gate current to a level insufficient to effect energization of the vend solenoids.

From the foregoing, it may be appreciated that the parallel gate current paths just discussed comprise an OR circuit which samples current through the various vend solenoids. Assuming for a moment that the sold-out switch 46 is establishing electrical continuity through its normally open contact (indicating depletion of articles in that column), then the soldout lamp 62 ,would be energized and gate current for the triac 64 would no longer be drawn through the solenoid 18. In this respect, it should be understood that the lamp current is also too small to cause operation of vend solenoid 18.

The OR function may be appreciated when it is considered that, as long as any one of the columns is not depleted of articles, gate current will flow to the triac 64 and the CREM 66 will remain energized. Therefore, the triac 64 is rendered nonconductive only when all of the columns are sold out, whereupon the CREM 66 is dcenergized to reject any coinage deposited.

Before proceeding with a discussion of the operation of the circuitry of FIG. 1. it is instructive to consider the exemplary dispensing mechanism 10 illustrated in FIG. 2. When the vend solenoid 18 is energized, its armature 20 moves to the left to swing the upper end of stop 22 upwardly through the opening 28 in platform 16; simultaneously, the roller 34 is moved out of engagement with tab 36 to release the gate 38. The cumulative effect of this action is to dispense the lowermost article since the weight thereof now causes clockwise movement of the gate 38, hence the lowermost article gravitates from the inclined platform 16 into a delivery chute (not shown) or other suitable delivery structure. The next article is retained against gravitation by engagement with the stop 22. Once the lowermost article clears the platform -16, the gate 38 swings in a counterclockwise direction under the action of the return spring 48 until it reaches a free position illustrated by the broken lines. At this time the projection 42 depresses the actuator arm 44 ofthe sold-out switch 46 which, in the instant example, causes momentary shifting of the switch contacts and energization of the sold-out lamp 62. This is only momentary, however, since deenergization of solenoid 18 (to be discussed) retracts the stop 22 and permits the previously retained article to roll down against the gate 38, the latter now assuming the full line position thereof with tab 36 bearing against the roller 34. It will be appreciated hereinafter that this momentary operation of the sold-out switch 46 executes the function of cancelling the previously established credit. ln the event that there is no additional article to roll down against the gate 38, the sold-out lamp 62.would remain energized to signal the customer and the circuitry now functions to prevent loss of credit in the event that the customer should now select the depleted column.

Returning to the circuitry of FIG. 1 and assuming that none of the columns is depleted, the deposit of appropriate coinage effects momentary actuation of coin switch 78 to, in turn, gate the SCR 88. The gate current path for SCR 88 extends via resistor 94, diode 84, and resistor 90. The capacitor 86 charges to maintain the SCR 88 in conduction when the contacts of the coin switch 78 are at dead break on return of the switch to normal. Conduction of the SCR 88 energizes relay coil 76 to pull in the credit relay and establish credit in the machine.

With the relay coil 76 energized, the relay switches 72 and 74 now make electrical continuity through their normally open contacts. the operation of switch 72 thus serving to interrupt the flow of gate current to the triac 64. This deenergizes the CREM 66 to preclude acceptance of coinage until the close of the vend cycle. Additionally, a holding circuit for the gate of the SCR 88 (necessary since SCR 88 is in an AC circuit) is established as follows: From line 54 through the normally closed contact of coin switch 78, through the normally open contact of relay switch 74, through the series connected solenoid holding switches 32, 32a and 32b, through the resistor 102 to relay switch 72, through the normally open contacts of the latter along lead 82 to the diode 84, and thence to the gate of SCR 88 via resistor 90.

The customer is now free to make a selection. Assuming that selector switch 580 is actuated, line 54 is effectively connected with solenoid 18a through the sold-out switch 46a by virtue of the following circuit: From the coin switch 78 to relay switch 74, through the series connected solenoid holding switches 32, 32a and 32b, along lead 100 to selector switches 58b and 58a, and along lead 600 to the sold-out switch 46a and the solenoid 18a. When the push button switch 58a is released by the customer, the solenoid 18a remains energized by virtue of a holding circuit through its now actuated holding switch 32a. Should the selector switch 58a be released at the time that the holding switch 32a is shifting its contacts, the capacitor 86 will maintain the SCR 88 energized during the dead break condition of switch 32a. A new holding circuit for the SCR 88 is now established through the actuated holding switch 32a, the sold-out switch 460, lead 60a, and resistor a.

As the lowermost article is dispensed and moves clear of the gate 38 of the respective column, the gate returns to its free position illustrated in broken lines as discussed above. Assuming that the column is not now depleted, momentary actuation of the sold-out switch 46a occurs to break the holding circuit for the SCR 88 just set forth above. This dcencrgizes the relay coil 76 to cancel the established credit, whereupon the circuitry returns to standby and triac 64 is again rendered conductive.

Assuming now for purposes of illustration that the article just vended by solenoid 18a was the last article in stock in the column, it will be appreciated that the sold-out switch. 460 remains closed against its normally open contact and the sold out lamp 620 is continuously energized This warns the customer that the column is sold out. but in the event that he should establish credit and depress the selector switch 58a inadvertently, the established credit is not lost since the lead 600 is now disconnected from the solenoid 18a. Therefore, since there is no way that solenoid 18a can be energized, the credit relay remains pulled in and the customer is free to select another article from an undepleted column.

In summary, the sold-out switches 46, 46a and 46b effect the performance of the following functions: I

l. Deencrgization of the CREM 66 when all selections are soldout;

2. Operation of the sold-out lamp 62, 62a or 62b for each particular selection;

3. Inhibiting of the selector switches 58, 58a and 58b as appropriate so that a sold-out selection cannot be purchased; and

Q 4. Cancellation of credit by interrupting the holding circuit for the SCR 88 existing at the time that the gate 38 of the selected column moves to its free position.

Although the circuitry for only three columns is illustrated in FIG. 1, it should be understood that as many columns as desired may be controlled by the addition of a selector switch, sold-out switch, vend solenoid, and solenoid holding switch for each added column, together with the interconnecting circuitry as illustrated. It is particularly noteworthy that, as the number of columns are increased, it is only necessary in the instant invention to add a single sold-out switch for each column since the triac 64 and the SCR 88 are common to all of the columns ofthe machine regardless ofnumber.

lclaim:

1. In a multiple selection article vending machine:

a plurality of selectively operable structures for dispensing articles from the machine;

electrically controllable means for establishing credit in response to acceptance of money deposited in the machine;.

a plurality of article-sensing sold-out switches operably associated with respective structures and said credit establishing means;

each sold-out switch being responsive to depletion of articles dispensed by the associated structure and, upon sensing of article depletion, preventing loss'of established credit if the customer should select the depleted articles, whereby the customer is permitted to choose another selection which is not sold out;

deposit accept-reject means having a first, standby condition in which deposits of money in the machine are accepted to permit establishment of credit by said credit establishing means, and a second condition in which said deposits are rejected to prevent the establishment of credit;

an electrically responsive control device common to all of said structures and coupled with said accept-reject means; and

circuit means intercoupling said sold-out switches and said device for operating the latter to maintain the accept-reject means in its first condition prior to the deposit of money as long as at least one of said sold-out switches does not sense article depletion, and for operating the device to cause the accept-reject means to assume the second condition thereof when all of said sold-out switches sense the depletion of articles, thereby preventing the establishment of credit until the machine is resupplied with articles.

2. in a vending machine as claimed in claim 1, each sold-out switch effecting cancellation of established credit after initiation of dispensing of an article by the respective dispensing structure.

3. In a vending machine as claimed in claim I:

each ofsaid structures being electrically operated;

said device having a control connection for receiving operating current for the device to cause the latter to maintain the accept-reject means in said first condition thereof;

said circuit means connecting each of said sold-out switches in series relationship with the respective structure and said control connection for flow of said operating current through each of said structures whose associated sold-out switch is not sensing article depletion; and

said circuit means having means for limiting the magnitude of said current to a level insufficient to operate said structures.

4.1a a vending machine as claimed in claim 3:

said accept-reject means including an electrically responsive actuator; and

said device comprising a solid state switch for controlling energization of said actuator.

5. In a multiple selection article vending machine:

a plurality of selectively operable structures for dispensing articles from the machine; i

electrically controllable means for establishing credit in response to acceptance of money deposited in the machine;

a plurality of article-sensing sold-out switches opcrably associated with respective structures and said credit. establishing means;

each sold-out switch being responsive to depletion of articles dispensed by the associated structure and effecting cancellation of established credit after initiation of dispensing of an article by the associated dispensing structure;

deposit accept-reject means having a first, standby condition in which deposits of money in the machine are accepled to permit establishment of credit by said credit establishing means, and a second condition in which said deposits are rejected to prevent the establishment of credit;

an electrically responsive control device common to all of said structures and coupled with said accept-reject means; and

circuit means intercoupling said sold-out switches and said device for operating the latter to maintain the accept-reject means in its first condition prior to the deposit of money as long as at least one of said sold-out switches does not sense article depletion, and for operating the device to cause the accept-reject means to assume the second condition thereof when all of said sold-out switches sense the depletion of articles, thereby preventing the establishment of credit until the machine is resupplied with articles.

6. in a vending machine as claimed in claim 5:

each of said structures being electrically operated;

said device having a control connection for receiving operating. current for the device to cause the latter to maintain the accept-reject means in said first condition thereof;

said circuit means connecting each ofsaid sold-out switches in series relationship with the respective structure and said control connection for flow ofsaid operating current through each of said structures whose associated sold-out switch is not sensing article depletion; and

said circuit means having means for limiting the magnitude ofsaid current to a level insufficient to operate said structures.

7. in a vending machine as claimed in claim 6:

said accept-reject means including an electrically responsive actuator; and

said device comprising a solid state switch for controlling energization of said actuator.

8. in a vending machine as claimed in claim 5:

and a plurality of shiftable article delivery members cooperating with respective structures to effect successive dispensing of articles upon repeated operation of each of said structures;

each of said members having a standby position and, upon operation of the respective structure, first moving" to an article delivery position and subsequently to a third position prior to return movement thereof to said standby position; and

each sold-out switch being disposed for operation by the respective member to effect the cancellation of established credit when the member moves to said third position thereof.

9. in a multiple selection article vending machine:

a plurality of selectively operable structures for dispensing articles from the machine;

electrically controllable means for establishing credit in response to acceptance of money deposited in the machine;

a plurality of article-sensing sold-out switches operably associated with respective structures and said credit means and each effecting cancellation of established credit after initiation of dispensing of an article by the associated dispensing structure;

a plurality of shiftable article delivery members cooperating with respective structures to effect successive dispensing of articles upon repeated operation of each of said structures;

each of said members having a standby position and, upon operation of the respective structure, first moving to an article delivery position and subsequently to a third position prior to return movement thereof to said standby position;

each sold-out switch being disposed for operation by the 

